Hi,
>CDMA - low energy, shorter wave amplitude, shorter distances, requires more towers, weaker handoffs between cells (???), more overall potential capacity, higher cost buildout.
Unfortunately, your comprision between CDMA and TDMA is flawed.
I am not a Electrical Eng. but have been following the CDMA/TDMA debate for a long time (about 3 years now).
Here are some things I find that are wrong :
(Also, visit the QCOM thread...there are people there who are very familiar with this debate and will be able to give you an even better perspective)
1) Strong handoff vs. weaker handoff (as you claimed)
Well it is actually Hard Handoff vs. Soft Handoff.
(TDMA with Hard Handoff and CDMA with Soft Handoff)
Hard Handoff is bad because it results in clicks and more dropped
calls. While Soft handoff provides seemless handoffs.
This is an advantage of CDMA (but would not seem so if it were called "weaker handoff ;-)
2) low overall energy and shorter wave amplitude.
Same thing and a plus. You could increase this if you wanted, but why would you. This is an advantage of CDMA achieved due to spreading.
3) More towers and Higher Buildout Cost????
Never herd of this. Please enlighten.
After 3 years my conclusion is that though TDMA systems are not bad and do a good job, they have some inherent problems like
a) More energy, less capacity.
B) Most importantly not very suited for higher data rates.
Thus, the result is that even the entrenched GSM (which has a form of TDMA air interface) camp in Europe is going to adopt a CDMA 3G system called W-CDMA.
-Raj
(Again I recommend anyone who wants to learn more about the CDMA/TDMA/GSM/WCDMA technologies to visit the QCOM thread here at SI.) |
